VESC Help Please! Motor Judder

Hi, can anyone tell me what’s wrong with the setup of this VESC please?

When it’s on the bench it all seems to work OK, but as soon as there’s a ‘load’ on the motor, it just judders. I’m sure it’s a setting but I just don’t know which one(s).


  • 2 x 3s 11.1v 25c Li-Po
  • Turnigy SK3 5065 236kv
  • VESC 4.12 (2.18 Firmware)
  • Mini Remote.

Try turning you motor max up to 80a And battery max to 50a

Thanks for the advice. Tried that just now but it’s still juddering…?

non sensored motors will stutter when starting up with load from dead stop. You’ll have to give it a kick start so it starts up smoother. You can also play around with increasing start up boost and min erpm to help with this.

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Can you give more detail on those settings options

start up boost is the minimum duty cycle when accelerating. Min erpm is as it states, the minimum erpm your motor will run at lowest duty cycle

Can I just be a complete noob here but what does ERPM stand for? I’m assuming ‘something’ revs per minute?

I’ll try playing with those settings. I’ve tried kicking off as well but that doesn’t seem to help…

electronic RPM. It’s the revolutions of pole pairs of the magnets in the motor. Most 50-63mm motors have 7 pole pairs, which means 1 mechanical RPM = 7 eRPM.

You’re saying you kick off with your foot on your board and accelerate and it doesnt do anything? You could try adjusting the battery cutoff start, it seems kind of high. You can set it to way below your actual cutoff while you’re testing.

electrical revs per minutes, it’s mechanical rpm multiplied with the number of pole pairs

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Thanks for the explanation!

I’ll try fiddling. What should the cutoff start/end be during normal use though?

Depends on your battery, Lipos tend to have higher cutoffs than cylinder cells. I’d probably go with 21~ for you, but it’d be best if you can find a data sheet for your particular pack.

OK, I think we’re making progress.

If I kick of now it’s working but ‘making progress’ is slow, much slower than with my old boat ESC anyway, which is good in a way but can I increase it slightly?

Also, the brake doesn’t really do much, makes a noise but it’s not actually braking me… does it matter how fast I’m going using the brakes?

Any help on the brakes would be very much appreciated? Not sure if this is the right setting but “Max brake current at dir change” is set to 10.

Just so we can follow your developpement, can you repost your new settings.

Batt min (regen) is your brakes

You’re pretty conservative with your current values (which is good!) but you can afford to up them a bit. Try 60/-60 for motor max/min. Up your battery max higher to about 40A~ as well.

Here’s my new settings…

I just loaded the defaults for 2.18 (standard) and the took it from there.

I upped my Motor max/min on @Namasaki 's advice

So to make them a bit more aggressive I’d up that value? More minus or more towards a positive figure?

try what @Jinra is suggesting

motor max: 60 motor min: -60 batt max: 40 batt min: -20

The lower the stronger (-60 is stronger than -40). I keep my max/min values exact opposites (eg. 60/-60) for the same amount of force when accelerating and braking.